Hope for coma patients

A chance observation in a coma patient study has revealed that doctors may soon be able to predict which patients will eventually wake up.

A neuropsychologist at Surrey University was looking back over some research on patients in a persistent vegetative state when she stumbled on the fact that all those who had subsequently recovered consciousness had shown tiny but detectable movements while unconscious. Those who were still in PVS had shown very few such movements.

PVS affects about 1,000 people in the United Kingdom. They are unaware of themselves or their environment but they do breathe spontaneously and show cycles of eye opening and closing.

The researchers, led by Sarah Wilson, had been studying PVS patients by recording every ten seconds some almost imperceptible movements such as tiny twitches of the toe or lifting of the foot.

The researchers, who worked with colleagues at the Royal Hospital for Neurodisability in London were investigating whether a new treatment for PVS patients has any immediate effect. The 24 patients had been in PVS for widely varying times - the longest was five years and the average was 16 months.

When Dr Wilson looked several months later to see what had happened to the patients she found that 12 had woken up, or "emerged". She found no difference between them and those who had not emerged in terms of how long they had been in PVS or their ages.

But there was one major difference. Those who had emerged had shown greater frequencies of the tiny body movements - many reaching the maximum recordable of six movements a minute compared with one movement a minute in those who did not emerge.

In addition, all the patients who later woke up had shown a surge in body movements just after the researchers arrived: "It's as though there was the beginnings of awareness there," said Dr Wilson.

"I'm sufficiently confident to say that that person should be regarded as potentially coming out of their vegetative state and that should influence treatment and management decisions." But without further research it was not possible to tell whether patients who show few movements are never going to emerge or whether they are simply at an earlier stage in a continuum.